JavaScript: Generate an array, containing the Fibonacci sequence, up until the nth term

JavaScript fundamental (ES6 Syntax): Exercise-237 with Solution

Fibonacci Sequence

Write a JavaScript program to generate an array containing the Fibonacci sequence, up to the nth term.

• Use Array.from() to create an empty array of the specific length, initializing the first two values (0 and 1).
• Use Array.prototype.reduce() and Array.prototype.concat() to add values into the array, using the sum of the last two values, except for the first two.

Sample Solution:

JavaScript Code:

// Define a function 'fibonacci' to generate Fibonacci sequence up to the specified length
const fibonacci = n =>
  Array.from({ length: n }).reduce((acc, val, i) => 
    acc.concat(i > 1 ? acc[i - 1] + acc[i - 2] : i), []); // Generate Fibonacci sequence

// Test the 'fibonacci' function with different lengths
console.log(fibonacci(2)); // Output: [0, 1]
console.log(fibonacci(3)); // Output: [0, 1, 1]
console.log(fibonacci(6)); // Output: [0, 1, 1, 2, 3, 5]

Output:

[0,1]
[0,1,1]
[0,1,1,2,3,5]

Flowchart:

Live Demo:

See the Pen javascript-basic-exercise-237-1 by w3resource (@w3resource) on CodePen.

For more Practice: Solve these Related Problems:

• Write a JavaScript program that generates an array containing the Fibonacci sequence up to the nth term recursively.
• Write a JavaScript function that builds the Fibonacci sequence iteratively and returns an array of numbers.
• Write a JavaScript program that uses memoization to efficiently generate the Fibonacci sequence for large n.
• Write a JavaScript function that outputs the Fibonacci sequence in a functional programming style using reduce().

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